Gas burner



July 5, 1966 H1.. KoEHRER A 3,259,170

GAS BURNER Filed June 12, 1964 32 -Q- United States Patent O 3,259,170 GAS BURNER Henry L. Koehrer, St. Louis, Mo., assigner to McQuay- Norris Manufacturing Company, St. Louis, M0., a corporation of Delaware Filed June 12, 1964, Ser. No. 374,676

5 Claims. (Ci. 158-118) This invention relates generally to gas burners for use in various gas-fired appliances, particularly laundry dryers.

Burners of the character referred to are commonly applied to the end of a gas supply line, and include ports for admitting air into a confined zone through which the gas stream is flowing, and for mixing the two together a short distance away from a position at which the combustible stream is ignited. A typical such gas burner is composed of a tubular member connected, vat one end, to a gas supply line, and having thereadjacent a ported chamber through which air is admitted into concurrent flow with the stream of gas emerging from the supply line. As the streams of gas rand air flow toward the other end of the tubular member, they pass through -a constriction having a venturi action which thoroughly mixes the streams of air and gas before they reach the end of the tubular member at which combustion occurs.

Devices of the character aforesaid, as heretofore manufactored, have involved the drawing of tubes and the carrying out of spinning operations thereon to provide the constriction and the proper conformation of the air inlet chamber as Well as the tip; and have also involved the formation of cup-shaped parts or sleeves for mounting the tube upon the gas supply line and/or adjusting the effective size of ports through which air is admitted into the tubular member. These are costly and tedious manufacturing operations.

It is the object of the present invention, generally stated, to provide a gas burner of the character aforesaid, and method of making the same, which will reduce the cost of manufacturing such devices.

The invention contemplates, generally, that the customary tubular member be composed of metal stampings or molded parts, preferably two identical halves each embracing half of the circumference of the tubular member. Such halves may be readily manufactured by stamping. For example, given a female `die having a cavity contrageneric with half the exterior contour of such a tube, and given a male die having a convexity contrageneric with half the interior contour of the tube, a iiat metal sheet may be stamped between such dies, and two such stampings may be assembled together to quickly, easily and cheaply provide such a tube having the desired conguration to form the connection with the gas supply line, the air inlet chamber, the venturi, the tip, and inter vening portions. The air inlet chamber may be ported by a single punching operation, preferably carried out on the flat blank before it is die-formed.

The invention further contemplates a more economical control for the air inlets than has heretofore been provided. This is accomplished by conforming a at strip so as to have a length not greater than, and preferably less than, the interior circumference of the air inlet portion of the aforesaid tubular member; so as to have a width less than the axial dimension of the air inlet portion, but greater than the axial dimension of the ports in the air inlet portion of the tubular member; and bend- 3,259,170 Patented July 5, 1966 ICC ing it so that its length extends circumferentially and tits within the `air inlet .portion of the tubular member. Preferably, the strip is provided with a protuberance which may be in the form of -an out-turned integral tab fitting within one of the ports in the air inlet portion of the tubular member, and movable therein as a shutter so as to control the eifective area of said ports. Preferably, such a shutter is formed of a metal which has suiiicient inherent resilience that the radius thereof may 'be contracted, at least about a sixteenth of an inch, by diametrically addressed forces, without impairing its tendency to return to its initial condition when the forces are released. This characteristic permits the shutter strip to be manufacture-d slightly oversize with respect to the interior diameter of the air inlet portion of the tubular member, so that it must be contracted slightly to get it into position therein, but once in position, there is a sufficient inherent biasing force to maintain the shutter Ain snug, but sliding, relationship with respect to the interior of said air inlet portion.

An illustrative embodiment of the invention is shown in the accompanying drawings, in which:

FIGURE 1 is a view in one side elevation of a gas burner constructed in accordance with the present invention;

FIGURE 2 is a rview in another side elevation taken at right angles from FIGURE l;

FIGURE 3 is an end view (which, in operation, is usually the top view) of the burner sho-wn in FIGURES l and 2;

FIGURE 4 is a perspective view of a stamping, two -of which are utilized in the manufacture of the tubular portion of the burner shown in FIGURES 1 and 2;

FIGURE 5 is a `sectional view taken along line 5 5 of FIGURE l;

FIGURE 6 is a sectional View taken along line 6 6 of FIGURE 1; and

FIGURE 7 is a perspective view of the shutter member.

In the manufacture of a gas burner as shown in the drawings, two stampings 1 and 2 made from strips of appropriate sheet metal, and of the conformation shown in FIGURE 4, are assembled together to form a .tubular member having at one end a cylindrical nipple 3 for connection with a gas supply line; Vat the opposite end, `a constriction 4, defining an opening 5 of lesser diameter than the adjacent portion of the tubular member; a cylindrical air inlet chamber 6 having diametrically opposite ports 7 and 8, and a constriction 9 forming a yventuri between the `air inlet chamber 6 and the opening 5. The respective stampings 1 and 2 are identical, .that is to say, they may be -made in the same set of dies from identical blanks, and as shown most clearly in FIGURE 4, each such sta-mping has a portion 13 which defines half of nipple 3; an inturned lip 14 which denes half of constriction 4; 'a semicircular edge 15 which defines half of opening 5; a ported semicy'lindrical part 16 which defines hal-f of the cylindrical air inlet chamber 6, yand all of one of ports 7 or 8 therein; and a constriction of semicircular crosssection 19 dening half of the venturi 9. Additionally, each of the stampings 1 and 2 has oppositely extending flanges, 11 and 12 on stamping 1, and 21 and 22 on stamping 2. The anges 11 and 21 are identical with each other, and the flan-ges 12 and 22 are identical with each other, and, preferably, the flanges 11 and 12 are righthand and lefthand versions of each other. The anges 11, 12, 21 and 22 provide a means whereby the stampings 1 and 2 may be connected together, as by welding, riveting, or any other appropriate means, to form a composite tubular member split in the axial direction of Ithe two identical halves 1 and 2.

Within 'the air inlet chamber 6, there is provided a shutter 23, preferbaly formed of sheet brass, or other appropriate metal having substantial inherent resilience. The shutter 23 has a width, `between edges 24 and 25 thereof, less than the axial dimension of air inlet chamber 6, but greater than the axial dimension of ports 7 and 8. In the form shown, the shutter 23 is an incomplete cylindrical sleeve whose outside diameter, in its free and unconned condition, is slightly greater, by, say, a sixteenth of an inch, lthan the inside diameter of air inlet chamber 6. The shutter is, however, readily contractible, so as to be received within the air inlet chamber 6, and its inherent resilience biases it outwardly into engagement with the interior walls of air inlet chamber 6. In the form shown, the shutter 23 is provided with a tab 26 projecting outwardly therefrom, and dimensioned so as to be readily receivable within one or the other of ports 7 or 8 and to pass through the same, as clearly shown in FIGURES 5 and 6. The tab 26 not only provides an exteriorly accessi-ble means for rotating shutter 23 about the axis of the air inlet chamber and relative thereto, but also limits the axial movement of the shutter relative to the air inlet chamber 6, so as to maintain opposite edges 24 and 2S of the shutter at all times axially endward of the margins of at least part of ports 7 and 8. In other words, the differential in axial length ybetween tab 26 and openings 7 or 8 is preferably less than the differential in axial length between the ports 7 and 8, on the one hand, and the distance between opposite edges 24 and 25, on the other hand. Such an arrangement permits of some relative axial movement of the shutter 23 within air inlet chamber 6, but such axial movement is limited by tab 26 so as to prevent the movement of edges 24 and 25 into position where they are exposed through ports 7 or 8. In the embodiment shown, the shutter 23 is provided with a port 27, whose area corresponds substantially to that of ports 7 and 8; and diametrically opposite port 27, there is a space 28 between tab 26 and the opposite extremity 29 of shutter ter with port 7, thereby reducing the inflow of air to the m'mimum, which is, in fact, only leakage. Any intermediate position of tab 26 between the full line and dotted line position, shown in FIGURE 6, thus leaves ports 7 and 8 partially open, and consequently provides for the desired adjustment in air intake. In the embodiment shown, the diametrically opposite ports 7 and 8 each embrace about a quadrant of the circumferance of air inlet chamber 6, while the port 27 and the open space 28 have substantially the same angular extent. Between port 27 and tab 26, as well as between port 27 and extremity 29, the shutter 23 is preferably imperforate, but it will be understood that if the parts are so snug fitting that insufficient air to properly support combustion is admitted when the shutter is in the dotted line position shown in FIGURE 6, small perforations may be made in I the portions of shutter 23 shown in the drawings as irnperforate.

When a burner of the character described is used in situations which require a spreading flame, a suitable bathe may be attached in spaced relationship withopening 5. An appropriate bamle is illustrated in FIGURES 1, 2 and 3, and consists of a canopy 30 having a pair of legs 31 and 32, which may be connected as by rivets, welding, or bolts, to the opposite flanges 11-22 and 12-21 of the composite tubular member. In the form shown, the -marginal portions of the canopy 30 are tilted upwardly relative to its central section, thereby tending to spread the flame radially outward and axially away from the burner tip as represented by mouth 5.

In the manufacture of the burner, the shutter 23 is encaged within `the opposite halves of the air inlet chamber 6 before the stampings 1 and 2 are secured together at their anges 11-22 and 12-21. If said flanges are to be connected together by welding, it is preferable that the shutter 23 be made of a metal different, or at least having dilferent Welding characteristics, from that of stampings 1 and 2, in order to avoid inadvertent attachment of the shut-ter to either or both of stampings 22 during the course of welding. Where the stampings 1 and 2 are connected together by rivets or by bolts, it is desirable that the usual precautions .be exercised to produce a gas-tight seal between the contiguous faces of flanges 11 and 22 on one side, and 12 and 21 on the other side; and, indeed, when such precautions are taken, the stampings 1 and 2 may be connected by spot welding.

From the foregoing description, those skilled in the art should readily understand that the invention accomplishes its object, and produces a burner which is advantageously economical to manufacture, but, at the same time, provides a wide range of adjustment of air intake, ease of accomplishing such adjustment, and facility of connection to a gas supply line. While one complete embodiment of the invention has been disclosed in detail, it is to be understood that the invention is not limited to the detail of the disclosed embodiment. On the contrary, those skilled in the art will readily perceive of modifications and variations utilizing the principle of the invention, without departing from the spirit thereof or the scope of the appended claims.

Having thus described the invention, what is claimed and desired -to be secured by Letters Patent is:

1. In a burner for gas-burning appliances having an outlet, a `gas inlet, and a venturi between the outlet and the inlet, -a cylindrical cham-ber between said inlet and said venturi, said chamber having a circumferential port to admit air thereto, and lmeans to regulate the flow of air through said port comprising, an incompletely cylindrical shutter within said chamber and having a sliding fit therewithin, said shutter having axial and circumferential dimensions less than that of said cylinder but greater than that of said port, and part of said shutter extending through said port to limit relative rotation between asid shutter and said chamber about the axis of the latter.

2. The combination of claim 1 wherein said chamber has diametrically opposite ports, said par-t of said shutter is at a circumferential terminus thereof, and said shutter has a port which is aligned with one of said chamber ports when said part is adjacent one edge of the other of said chamber ports, and which shutter port is disaligned with the rst-mentioned chamber port when said part is adjacent the opposite margin of the second-mentioned chamber port.

3. A gas-burner comprising, an axially split tubular member composed of identical halves secured together along the split, each end of said member having an opening of lesser cross-section than the adjacent parts of said member, said member being formed to provide a venturi between the ends of said mem-ber and a ported cylindrical chamber between said venturi and one end of said member, and an incompletely cylindrical shutter within said chamber and movable relative to the ports there- 1n.

4. The burner of claim 3 wherein the shutter is resiliently biased against the interior walls of said chamber.

5 6 5. The method of making `a gas burner comprising, References Cited by the Examiner forming two identical stampings each defining an axially UNITED STATES PATENTS divided half of a tubular member, and each having a semicylindrical enlargement near .one end yand a con- 6991302 :JK/1.901 Franklin 158-118 X struction intermediate its ends, forming a port in said 5 1,035,639 8/1912 Reckef 158-118 semicylindrical enlargement, forming an incompletely 1,537,335 5/1925 Cross 158-119 cylindrical shutter having a port therein, mounting the 3,184,337 5/1965 Craemer 158-115 X shutter in 4the semicylindrical enlargements in one'cf said FOREIGN PATENTS stampmgs, brlngmg the other stamping into posmon to 197,182 5/1923 Great Britainencage said shutter in the semicylindrical enlargements 10 of both stampings, and while the shutter is so encaged, JAMES W WESTHAVER Primary Examiner securing the sampings together. 

1. IN A BURNER FOR GAS-BURNING APPLIANCES HAVING AN OUTLET, A GAS INLET, AND A VENTURI BETWEEN THE OUTLET AND THE INLET, A CYLINDRICAL CHAMBER BETWEEN SAID INLET AND SAID VENTURI, SAID CHAMBER HAVING A CIRCUMFERENTIAL PORT TO ADMIT AIR THERETO, AND MEANS TO REGULATE THE FLOW OF AIR THROUGH SAID PORT COMPRISING, AN INCOMPLETELY CYLINDRICAL SHUTTER WITHIN SAID CHAMBER AND HAVING A SLICING FIT THEREWITHIN, SAID SHUTTER HAVING AXIAL AND CIRCUMFERENTIAL DIMENSIONS LESS THAN THAT OF SAID CYLINDER BUT GREATER THAN THAT OF SAID PORT, AND PART OF SAID SHUTTER EXTENDING THROUGH SAID PORT TO LIMIT RELATIVE ROTATION BETWEEN SAID SHUTTER AND SAID CHAMBER ABOUT THE AXIS OF THE LATTER. 